Method of forming brake drums



1934- J. w. VANDERVEER 1,970,027

METHOD OF FORMING BRAKE DRUMS Filed April 22] 1951 1N VEN TOR.

BY 77 %V/ 'ATToRNEYs.

Patented Aug. 14, 1934 UNITED STATES PATENT OFFICE 1 'Claim.

Brake drums have heretofore been made all of cast metal, that is, thebrake ring and the disc supporting it. It has also been proposed to makebrake drums provided with a cast ring and a sheet 5 metal discsupporting the ring, the connection between the disc and the ring beingaccomplished in the casting operation. This forms a desirable brakedrum, but is subject to serious losses through strains set up in thecooling of the cast ring with relation to the sheet metal disc. Thepresent invention is designed to form brake drums utilizing a sheetmetal disc and a cast ring connecting them in a simple, but substantialmanner without placing the ring under objectionable strains. Featuresand details of the invention will appear from the specification andclaim.

A preferred embodiment of the invention and manner of forming the sameis illustrated in the accompanying drawing as follows:-

Fig. 1 is a section on the line 1-1 in Fig. 2.

Fig. 2 a side elevation of the drum.

Fig. 3 an elevation of an attaching plug.

Fig. '4 a central section of a modification.

Fig. 5 a mold showing the manner of forming the ring illustrated in Fig.4.

1 marks the brake ring. This has an internal rib 2 on its innerperiphery, this rib having slight enlargements at 3 and being providedwith periorations, or openings 4. These openings are countersunk forminga shoulder 5.

A sheet metal disc 6 is struck up having the usual annular shoulders andbeing adapted for the usual mounting. It is preferably of sheet steel,or at least weldable material.

The disc seats against the rib 2. A plug '7 is arranged in the opening4, the plug preferably conforming to the shape of the opening and issecured-to the disc by spot welding, the spot welding being accomplishedas indicated by the electrodes 8. The plug '7 may be made in a singlepiece, or it may be in the form of two punched discs, the spot weldingnot only uniting the plug with the disc 6, but also uniting the parts ofthe lug. By this arrangement, the ring 1 'may be 5 cast and is free fromshrinkage strains, turned accurately and provided with the disc withoutintroducing strains to the structure. Thus a cast brake drum with itsadvantages particularly as to scoring and as to chatter may beaccomplished in a cheap and reliable manner in that the losses inproduction are very slight and the ring is stronger in use in that itdoes not have initial strains.

In the modified form in Fig. 4 the brake ring 9 has an internal rib 10.In the casting of this rib 76 the plugs 11 of weldable material areplaced in the mold, as shown in Fig. 5, and secured in the rib 10 in thecasting operation. Otherwise the structure is similar to that shown inFig. 1. The disc 6 is seated against the rib 10 and the plug 11 I iswelded to the disc by spot welding through the electrodes 8.

What I claim as new is:-

The method of forming a brake drum which consists in shaping a metaldisc of weldable as material, casting a brake ring around a com nectingpiece, and welding said piece to said disc.

JEWELL W. VANDERVEER.

